Design and Stress Analysis of Extraterrestrial ... - The Black Vault

Soldering the porous plate with the housing is more desirable
since cracking of the emitter is less likely. In soldering, the
housing and the rmitter are heated simultaneously.
) (a)
(b) 6
ow
C) (d)
Fig. 5.38.
Icn emitter design.
The shape of emitter plates, illustrated in Fig. 5.38a, b, c, has
disadvantages. The high temperature of the plate (12000C) requires
an even higher temperature for the heater (up to 17000C) and,
cknsequently, the work of the motor is accompanied by large heat
losses since the porous plate is comparatively large.
The emitters shown in Fig. 5.38a are also bad because of the fact
that their uniform heating cannot be ensured. The drum-cover plates,
installed for beam shaping, have temperatures, unlike porous tungsten
temperatures, which correspond to the appearance of cracks in the
unit.
A more perfected design is presented in Fig. 5.38d. The radiation
surface is reduced to a minimum. Some increase in the length of the
soldered surface as compared with the preceding designs is compensated
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